Adding repo after 2 days of vibecoding

public/src/planetGeneration.js

@@ -0,0 +1,76 @@
+import * as stat from "./planetStat.js";
+
+const getRandomInt = (rng, min, max) => Math.floor(rng() * (max - min + 1)) + min;
+const pick = (rng, array) => array[Math.floor(rng() * array.length)];
+
+const randomPlanetTypeKey = (rng, planetType) => {
+  const keys = Object.keys(planetType);
+  return keys[Math.floor(rng() * keys.length)];
+};
+
+const distributePercentages = (rng, items) => {
+  if (items.length === 0) return {};
+  if (items.length === 1) return { [items[0]]: 100 };
+
+  const cuts = Array.from({ length: items.length - 1 }, () => rng()).sort((a, b) => a - b);
+  const segs = cuts.map((p, i) => (i === 0 ? p * 100 : (cuts[i] - cuts[i - 1]) * 100));
+  segs.push((1 - cuts[items.length - 2]) * 100);
+  return Object.fromEntries(items.map((item, idx) => [item, segs[idx]]));
+};
+
+export function buildPlanetTypeDistributions(rng) {
+  for (const key in stat.planetType) {
+    const type = stat.planetType[key];
+    if (Array.isArray(type.elements)) type.distributedElements = distributePercentages(rng, type.elements);
+    if (Array.isArray(type.resources)) type.distributedResources = distributePercentages(rng, type.resources);
+  }
+}
+
+export function generatePlanet(rng) {
+  // Distributions are normally created once at startup, but since we run per-cell with per-cell rng,
+  // we generate per planet for stable, deterministic results from the same seed.
+  buildPlanetTypeDistributions(rng);
+
+  const planetTypeGeneration = randomPlanetTypeKey(rng, stat.planetType);
+  const planetName = pick(rng, stat.planetNamePrefix) + pick(rng, stat.planetNameSuffix); // don't touch it
+  const planetPopulationPeople = pick(rng, stat.planetType[planetTypeGeneration].populationType);
+  const planetPopulationNumber =
+    (stat.planetType[planetTypeGeneration].population * getRandomInt(rng, 50, 150)) / 99.9;
+
+  return {
+    name: planetName,
+    type: planetTypeGeneration,
+    population: {
+      billions: Number(planetPopulationNumber.toFixed(3)),
+      majority: planetPopulationPeople,
+    },
+    production: stat.planetType[planetTypeGeneration].distributedElements,
+    naturalResources: stat.planetType[planetTypeGeneration].distributedResources,
+  };
+}
+
+export function formatPlanet(planet) {
+  const elementsDescription = Object.entries(planet.production)
+    .map(([k, v]) => `    ${k}: ${v.toFixed(1)}%`)
+    .join("\n");
+
+  const resourcesDescription = Object.entries(planet.naturalResources)
+    .map(([k, v]) => `    ${k}: ${v.toFixed(3)}%`)
+    .join("\n");
+
+  return `Planète : ${planet.name}
+
+Type : ${planet.type}
+
+Production :
+${elementsDescription}
+
+Ressources naturelles :
+${resourcesDescription}
+
+Population :
+
+    ${planet.population.billions.toFixed(3)} milliards
+    Majoritairement ${planet.population.majority}`;
+}
+